ASTM E3101-18

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: E3101 − 18
Standard Practice for
Microwave Examination of Polyethylene Butt Fusion Joints
This standard is issued under the fixed designation E3101; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
1.1 This practice covers microwave (MW) examination of
1.9 This international standard was developed in accor-
buttfusionjointsmadeentirelyofpolyethyleneforthepurpose
of joining polyethylene piping or vessel parts. dance with internationally recognized principles on standard-
NOTE 1—The notes in this practice are for information only and shall
ization established in the Decision on Principles for the
not be considered part of this practice.
Development of International Standards, Guides and Recom-
NOTE 2—This practice references HDPE and MDPE for pipe applica-
mendations issued by the World Trade Organization Technical
tions as defined by Specification D3350.
Barriers to Trade (TBT) Committee.
1.2 MW examination detects differences between the di-
electric constant(s) of the materials being examined. These
2. Referenced Documents
differences may be due to material construction (expected) or
flaws such as voids, cracks, or foreign material intrusion 2.1 ASTM Standards:
(unexpected). D3350Specification for Polyethylene Plastics Pipe and Fit-
tings Materials
1.3 The butt fusion joining process can be subject to a
E543Specification forAgencies Performing Nondestructive
variety of flaws including, but not limited to, lack of fusion,
Testing
particulate contamination, inclusions, and voids.
E1316Terminology for Nondestructive Examinations
1.4 This practice is intended for use on polyethylene butt
F2620PracticeforHeatFusionJoiningofPolyethylenePipe
fusion joints of pipe diameters of 4in. to 65in. (100mm –
and Fittings
1650mm) and wall thickness of 0.5in. to 4in. (12mm –
F2634Test Method for Laboratory Testing of Polyethylene
100mm).Greaterandlesserthicknessesandsmallerdiameters
(PE) Butt Fusion Joints using Tensile-Impact Method
may be tested using this standard practice if the technique can
be demonstrated to provide adequate detection on mockups of
2.2 ASNT Documents:
the same wall thickness and geometry.
Recommended Practice SNT-TC-1A for Nondestructive
Testing Personnel Qualification and Certification
1.5 This standard practice does not address microwave
ANSI/ASNT CP-189Standard for Qualification and Certifi-
examination of electrofusion joints, socket joints, or saddles.
cation of Nondestructive Testing Personnel
1.6 This standard details inspection requirement only.
Accept/reject criteria must be established contractually and is 2.3 Military Standard:
typically done using multiple samples with mechanical test MIL-STD-410Nondestructive Testing Personnel Qualifica-
(that is, tensile test) validation.
tion and Certification
1.7 Thevaluesstatedininch-poundunitsaretoberegarded
2.4 AIA Document:
as standard. The values given in parentheses are mathematical
NAS 410Certification and Qualification of Nondestructive
conversions to SI units that are provided for information only
Testing Personnel
and are not considered standard.
1.8 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
responsibility of the user of this standard to establish appro- contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
AvailablefromAmericanSocietyforNondestructiveTesting(ASNT),P.O.Box
This practice is under the jurisdiction of ASTM Committee E07 on Nonde- 28518, 1711 Arlingate Ln., Columbus, OH 43228-0518, http://www.asnt.org.
structive Testing and is the direct responsibility of Subcommittee E07.10 on AvailablefromStandardizationDocumentsOrderDesk,Bldg.4SectionD,700
Specialized NDT Methods. Robbins Ave., Philadelphia, PA 19111-5094, Attn: NPODS.
Current edition approved Nov. 1, 2018. Published December 2018. DOI: Available from Aerospace Industries Association (AIA), 1000 Wilson Blvd.,
10.1520/E3101-18. Suite 1700, Arlington, VA 22209, http://www.aia-aerospace.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E3101 − 18
2.5 Welding Authority Documents: 3.1.10 medium density polyethylene (MDPE), n—a tough,
AWS G1.10M:2016Guide for the Evaluation of Thermo- flexible, thermoplastic resin made by polymerizing ethylene,
3 3
plastic Welds having a density range of >0.926 g/cm – 0.940 g/cm per
DVS Direction 2202-1 Imperfections in Thermoplastic Specification D3350.
Welded Joints; Features, Descriptions, Evaluation
3.1.11 MW transducer, n—an electronic device that gener-
atesanelectromagneticfieldinthemicrowavefrequencyrange
2.6 ISO Standard:
ISO-9712Non-destructive Testing – Qualification and Cer- (1 – 100 GHz) and is equipped with at least one microwave
detector that converts the microwave energy into voltage.
tification of NDT Personnel
3.1.12 polyethylene butt fusion joint, n—a joint made by
3. Terminology
holding the prepared squared ends of two pipes or pipe and
fitting against a heated plate per the conditions of a qualified
3.1 Definitions of Terms Specific to This Standard:
fusion procedure, which allows for the ends to be brought
3.1.1 Related terms are defined in Terminology E1316.
together after forming the proper melt, and then allowing the
3.1.2 cell classification, n—for polyethylene pipe resin, this
jointtocoolwhilemaintainingtheappropriateappliedforce.It
is a six digit code and letter describing the primary properties
is recommended that fusion procedures comply with Practice
that are considered important in the manufacture of PE piping,
F2620.
in the heat fusion joining of this material, and in defining the
3.1.13 probe, n—a MW transducer with a waveguide or
long-termperformancecapabilitiesandcolor/UVstability.The
other MW antenna enclosed in a fabricated container used
classification categories are defined in Specification D3350.
specifically for MW inspection.
3.1.3 cold fusion, n—a joint or a region within a joint in
3.1.14 scan,n—themovementoftheprobeinastraightline,
which there is little commingling of the polymer chains due to
usually along the long axis of the part being examined, where
reasons other than contamination.
data is collected.
3.1.4 dimension ratio (DR), n—this is the average outside
3.1.15 standoff, n—the radial distance from the outside
pipe diameter divided by the minimum wall thickness.
surfaceofthepipetobeexaminedtotheendoftheMWprobe
3.1.4.1 Discussion—The wall thickness increases when the
that is adjustable to provide proper examination of the joint.
DR decreases.
3.1.4.2 Discussion—Standard Dimension Ratio (SDR) is an
4. Summary of Practice
ANSI term to describe specific DRs in the series, that is, DR9,
4.1 This practice provides a general description of the
DR11, DR17, and others.
procedures to carry out microwave examination of polyethyl-
3.1.5 E plane, n—in the case of a linearly polarized probe,
ene butt fusion joints in piping systems.
this is the plane that contains the electric field and is at a right
4.2 This practice consists of bathing the butt fusion joint in
angle to the H plane.
a field of electromagnetic radiation at a specific frequency (or
3.1.6 H plane, n—in the case of a linearly polarized probe,
range of frequencies) in the microwave range using a MW
this is the plane that contains the magnetic field, and it is at a
Probe. This probe is passed over the butt fusion joint in a
right angle to the E plane.
controlled technique using a specified scan and index pattern
until the entire part or the region of interest has been com-
3.1.7 high density polyethylene (HDPE), n—a tough,
pletely covered. The reflected microwave energy is measured
flexible, thermoplastic resin made by polymerizing ethylene,
3 3
by the transducer along the scan lines and the resulting
having a density range of >0.940 g/cm – 0.965 g/cm per
Specification D3350. transducer voltage is recorded along with its position as
measuredbyscanandindexcoordinates.Uponcompletion,the
3.1.8 index, n—the movement of the probe in the circum-
voltage and position matrix is displayed by assigning either a
ferential direction at the completion of a scan line, typically in
false color range or a gray scale range to the voltages.
small increments, to position the probe to the start of the next
4.3 The image that is created is interpreted by a user
scan.
qualified per 6.2 and compared to scans generated from the
3.1.9 material designations, n—ashortenedcodetoidentify
reference components with the intent to non-destructively
the pipe material’s short-term and long-term properties.
assess the overall joint quality.
3.1.9.1 Discussion—Forpolyethylene,the“PE-XXXX”for-
4.4 Other analysis of the resulting measured voltages may
mat represents the density (1st digit), slow crack growth
be performed to gain additional information and assessment of
resistance (2nd digit), and Hydrostatic Design Stress (HDS,
the overall joint quality.
last two digits) where Specification D3350 is the reference.
4.5 This practice provides a method for routine inspection
of butt fusion joints prior to placing them in service as well as
6 for continuing in-service inspections of the joints.
Available from IHS, 15 Inverness Way East, Englewood, CO 80112, http://
www.global.ihs.com.
4.6 Examination results from the inspection using this
Available from International Organization for Standardization (ISO), ISO
practice may be used in combination with acceptance criteria
Central Secretariat, BIBC II, Chemin de Blandonnet 8, CP 401, 1214 Vernier,
Geneva, Switzerland, http://www.iso.org. based on workmanship or fitness for purpose.
E3101 − 18
5. Significance and Use 7. Surface Preparation
5.1 Polyethylenepipinghasbeenusedinsteadofsteelalloys 7.1 All inspection surfaces shall be clean and free of scale,
dirt,grease,paint,orotherforeignmaterialthatcouldinterfere
in the petrochemical, power, water, gas distribution, and
mining industries due to its resistance to corrosion, erosion, with interpretation of examination results. The methods used
for cleaning and preparing the surfaces for microwave exami-
and reliability. Recently, polyethylene pipe has also been used
for nuclear safety related cooling water applications. nation shall not be detrimental to the base material or the
surface finish. Excessive surface roughness or scratches can
produce signals that interfere with the examination.
6. Basis of Application
7.2 Warning—Do not use mechanical devices (such as
6.1 The following items are subject to contractual agree-
flapperwheels,grinders,sanders,etc.)tocleanPEweldsorany
ment between the parties using or referencing this standard.
part to be inspected. This action renders the part unacceptable
6.2 Personnel Qualifications:
for inspection.
6.2.1 Personnel performing examinations to this standard
7.3 Surfaces should be smooth and free of any deep
shall be qualified in accordance with a nationally recognized
grooves, gouges, dents, or other surface geometry that may
NDT personnel qualification practice or standard such as
adverselyimpacttheinspection.Surfaceflawsofsufficientsize
ANSI/ASNT CP-189, SNT-TC-1A, MIL-STD-410, NAS 410,
and/or depth that they appear in the scan image shall be noted
or a similar document. The practice or standard used and its
in the inspection report as “surface flaw.” The parties using or
applicable revision shall be identified in the contractual agree-
referencing this standard shall determine if the flaws are of
ment between the using parties. (Note that MW Inspection
sufficient depth to render the part unacceptable.
training requirements are specifically described in SNT-TC-
1A.)
8. Apparatus
6.2.2 Personnel shall be certified by the employer or certi-
8.1 A MW transducer with a single frequency, or a fre-
fying agency, as applicable.
quencyrangeifasweptfrequencydeviceisused,shallbeused
NOTE 3—MIL-STD-410 is canceled and has been replaced with NAS
for this examination. The frequency or frequency range se-
410;however,itmaybeusedwithagreementbetweencontractingparties.
lected shall be shown to be capable of detecting the reference
6.3 Qualification of Nondestructive Agencies:
flawsofthetypesdescribedinSection10totheextentrequired
6.3.1 NDT agencies shall be qualified and evaluated as
in the standardization and procedure qualification described in
described in Specification E543. The applicable edition of
Sections 11 and 12.
Specification E543 shall be specified in the contractual agree-
8.2 The transducer shall be mounted in a probe assembly
ment.
and shall be capable of detecting the reference flaws of the
6.4 Procedures and Technique—The procedures and tech-
types described in Section 10 to the extent required in the
niques to be used shall be as specified in the contractual
standardization and procedure qualification described in Sec-
agreement. It shall include at least the following information:
tions 11 and 12.
6.4.1 Type, dimensions, location, method of manufacture,
8.3 The stand-off and orientation (that is, E or H Field) of
and number of artificial flaws to be placed in the reference
the probe shall be capable of being adjusted to produce a
components.
satisfactory signal-to-noise ratio (S/N) for the detection of the
6.4.2 Method(s)formeasuringdimensionsofartificialflaws
required flaws as compared to background “noise” response
in the reference components and tolerance limits if different
fromirregularitiessuchassurfaceroughnessandagglomerates
than specified in Section 10.
of carbon black particles used for UV protection in the
6.5 Scope of Examination—Thescopeoftheexaminationas
polyethylene or other processing flaws.
defined in the report shall include these defined items:
8.4 Thefinalconfigurationoftheprobeandequipmentshall
6.5.1 Size and type of butt fusion joint to be examined.
be selected to produce a desirable S/N for the inspection. For
6.5.2 Number or percentage of joints to be examined.
example, the minimum value for the S/N for the smallest flaw
6.5.3 Thestage(s)inthemanufacturingprocessatwhichthe
inthereferencepipedescribedin10.4shouldbeatleast1.5.A
joints will be examined.
higherminimumvalueisdesirableandmaybespecifiedbythe
6.5.4 The surface condition of the inspected area.
contracting agency.
6.6 Reporting Criteria—Reporting criteria for the examina-
8.5 The equipment is set up such that the scan direction is
tion results shall be in accordance with Section 15 unless
axial to the pipe and the index is in the circumferential
otherwise specified. It shall include at least the following
direction. Select a scan speed and index that provides a
information:
reasonable total scan time without sacrificing S/N quality.
6.6.1 Requirements for permanent records of the response
Typically, a 0.1 in. (2.5 mm) index is chosen and a maximum
from each joint, if applicable.
index is considered to be 0.25 in. (6.4 mm).
6.6.2 Contents of examination report.
8.6 Encoderpositionalinformationiscalibratedandverified
6.7 Repaired/Reworked Items—Re-examinationofrepaired/ in both the circumferential and axial directions from a refer-
reworkeditemsisnotaddressedinthisstandardandifrequired ence start position and shall be accurate to within 1% of the
or permitted, shall be specified in the contractual agreement. total scan length or 0.4 in. (10 mm), whichever is less.
E3101 − 18
Calibration should be performed on a regular basis (for 10.3.3 The reference pipe shall be free of discontinuities or
example, daily) with verification occurring prior to the start of other conditions producing indications that can interfere with
any inspection. detection of the reference flaws.
10.3.4 Atleastoneofthereferencebuttfusedjointsshallbe
8.7 The position of the scanner shall be set such that the
maintained for dynamic standardization dur
...